Modeling of a Point Absorber for Energy Conversion in Italian Seas

Abstract

Abstract:In the present paper, we investigate the feasibility of wave electricity production in Italian seas by the deployment of the Seabased wave energy converter (WEC). A numerical model of the coupled buoy-generator system is presented, which simulates the behavior of the wave energy converter under regular waves of different wave heights and periods. The hydrodynamic forces, including excitation force, radiation impedance and hydrostatic force, are calculated by linear potential wave theory, and an analytical model is used for the linear generator. Two buoys of different radii are considered to explore the effect of buoy dimension on energy conversion and device efficiency. The power output is maximized by adding a submerged object to the floating buoy, in order to bring the system into resonance with the typical wave frequencies of the sites. The simulation results show a very good agreement with the published data on the Seabased WEC. The model is used to estimate energy production at eight Italian offshore locations. The results indicate that the degree of utilization of the device is higher than 20% at the two most energetic Italian sites (Alghero and Mazara del Vallo) and that it can be considerably increased if the floating body is connected to a submerged object, thanks to the resonant behavior of the WEC. In OPEN ACCESSEnergies 2013, 6 3034 this case, the degree of utilization of the device would be higher than 40% at most of the study sites, with the highest value at Mazara del Vallo. The work enlarges the perspective, to be confirmed by experimental tests and more accurate numerical modeling, on clean electric power production from ocean waves in the Italian seas.

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A new optimization procedure of heaving point absorber hydrodynamic performances

“…Ahn et al (2012) presented an innovative technology to generate energy from waves by the so-called hydrostatic transmission wave energy converter (HSTWEC), carrying out several simulations to investigate the working performance of the suggested device. Bozzi et al (2013) investigated the feasibility of wave electricity production in Italian seas, by the deployment of a sea-based wave energy converter, considering two buoys of different radii, in order to explore the incidence of WEC dimensions on both energy conversion and device efficiency, maximizing the power output by adding a fully submerged body that, in turn, brings the system into resonance with the typical wave frequencies of candidate deployment site. Finally, Yu et al (2014) analysed a set of three surge wave energy (OSWEC) converters, with the main aim of balancing design performances and costs due to manufacturing, deployment, operation, maintenance and environmental compliance, in a cost-driven design strategy.…”

Sustainability of the Renewable Energy Extraction Close to the Mediterranean Islands

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